Patent GB-303761-A (GB)
Title: Improvements in the production of hydrocarbons of low boiling point from those of high boiling point
IPC: C10C1/20
Filed: 1927-09-03
Abstract: 303,761. Johnson, J. Y., (I. G. Farbenindustrie Akt.-Ges.). Sept. 3, 1927, Hydrocarbons of low boiling-point are produced from hydrocarbons of higher boiling-point by treatment with a gaseous hydrogen halide at temperatures above 100‹ C. with or without pressure in presence of activated metals or alloys such as aluminium, copper, lead, magnesium, iron, cobalt, chromium and the like and their alloys. The activation is effected by treatment with solutions of metal salts, preferably after the surface has been etched with caustic soda, hydrochloric acid &c. and, if desired, washed with alcohol or ether. The activated metals may be used in admixture with anhydrous metal chlorides, particularly aluminium chloride. The initial materials may be tars, tar oils, mineral and shale oils, products of destructive hydrogenation of carbonaceous materials, and mineral oil fractions which are soluble in liquid sulphur dioxide; and the products may contain 20 to 30 per cent of benzene and toluene besides other light hydrocarbons. The yield of saturated aliphatic hydrocarbons of very low boiling-point may be increased by passing aliphatic or naphthenic hydrocarbons of high boiling point at low velocity; and the amount of the hydrohalogen acid may be increased by passing aliphatic. or naphthenic hydrocarbons of high boiling point at low velocity; and the amount of the hydrohalogen acid may be increased by passing it through the apparatus at a higher velocity, these methods yielding products boiling up to 70‹ C. The products may be recovered by strong cooling or compression or both, or by adsorption or absorption agents, preferably so as to secure a fractionation. The heat may be supplied by externally heating the reaction chamber, or by preheating the initial material; and inert gases such as hydrogen or nitrogen may be present. In the examples (1) crude Elwerat mineral oil is treated at 100-180‹ C. with dry hydrochloric acid in a vessel lined with monel metal in presence of aluminium turnings which have been treated with ether-alcohol, etched with caustic soda, and activated with uranium nitrate solution; (2) highboiling crude mineral oil is treated with hydrochloric acid gas at 400‹ C. in presence of cast-iron turnings activated with mercuric chloride; (3) producer-tar from brown coal is treated with hydrochloric acid gas at 150‹ C. in presence of granular aluminium activated by zinc chlorides ; (4) a fraction boiling at 200-400‹ C. of a product of destructive hydrogenation of coal is treated with hydrochloric acid at 120-160‹ C. in presence of aluminium turnings activated with copper chloride; (5) a mineral oil soluble in sulphur dioxide is treated with hydrochloric acid at 150-220‹ C. in presence of a mixture of aluminium turnings activated with uranium nitrate, and aluminium turnings activated with silver nitrate ; (6) a similar mineral oil is treated with hydrochloric acid at 170‹ C. in presence of aluminium chloride and granular aluminium activated with silver nitrate. Other examples show the influence of relative velocity of the acid and the hydrocarbon in presence of sheet aluminium activated with mercuric chloride, hydrocarbons from propane to hexane being the principal products. The hydrochloric acid and initial material may be reacted on the counterflow principle, for instance in a column. Specification 283,105 is referred to.